Mounting brackets for auxiliary suspension systems

ABSTRACT

Brackets for mounting auxiliary suspension systems, such as lift axle systems, to vehicles are disclosed herein. For example, brackets are disclosed for attaching lift axle hanger brackets and lift axle load springs to corresponding frame members. In some embodiments, the frame brackets can include physical features (e.g., a series of graduated steps in an edge portion thereof) to facilitate visual alignment of the lift axle with the vehicle frame members during installation. In other embodiments, the frame brackets can be two-piece brackets that enable the load springs to be removed and replaced without having to detach the frame bracket from the frame rail.

CROSS-REFERENCE TO RELATED APPLICATION(S) INCORPORATED BY REFERENCE

The present application claims the benefit of and priority to U.S.Provisional Patent Application No. 62/562,210, filed Sep. 22, 2017, andtitled “MOUNTING BRACKETS FOR AUXILIARY SUSPENSION SYSTEMS”, thedisclosure of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to brackets for attachingauxiliary suspension systems to the frames of trucks, trailers, andother heavy-lift vehicles.

BACKGROUND

Many heavy-duty trucks are designed to carry a wide range of loads thatvary depending on the type or amount of cargo they may be carrying. Tocarry the full range of loads, some trucks include one or more non-driverear axles in conjunction with one or more drive axles. The non-driverear axles may be needed for a variety of reasons, such as to complywith suspension and tire load ratings, bridge laws, etc. When the truckis unloaded, the non-drive axle is just “along for the ride,” since itis not needed to carry any load in that condition. For this reason, manytrucks use non-drive axles that can be lifted off of the ground and intoa stored position (the “lifted position” or “raised position”) when notneeded. This type of axle is often referred to as a “lift axle,” a“liftable axle,” an “auxiliary axle,” and/or an “auxiliary suspensionsystem.” By raising the lift axle when the vehicle is lightly loaded,wear on the lift axle tires can be reduced and fuel economy can beincreased due to the absence of rolling resistance from the lift axletires.

Lift axles can be installed ahead of or behind a drive axle on astraight truck or tractor. If a lift axle is positioned ahead of thedrive axle, the lift axle is referred to as a “pusher.” If the lift axleis positioned behind the drive axle, it is referred to as a “tag.” Liftaxles can also be installed ahead of or behind an axle or tandem axleson an articulating trailer. There are both steerable and non-steerablelift axles. As the name implies, the wheels on a non-steerable lift axlecannot turn left or right, and as a result non-steerable lift axles needto be raised prior to turning a tight corner or the tires will scuff andimpose high lateral stresses on the wheels and other chassis components.In contrast, steerable lift axles include wheels that can caster so theyturn and can remain in contact with the ground during tight turning.Various lift axle systems and associated components are described inU.S. Pat. No. 5,403,031 to Gottschalk et al., U.S. Pat. No. 6,073,947 toGottschalk et al., U.S. Pat. No. 6,311,993 to Hulstein et al., U.S. Pat.No. 6,880,839 to Keeler et al., U.S. Pat. No. 9,352,628 to Barton etal., and U.S. Pat. No. 9,688,318 to Wetter et al., each of which isincorporated herein by reference in its entirety.

Lift axle systems are typically attached to the chassis of a truck orother vehicle by a set of brackets. For example, some lift axle systemsinclude two forward hanger brackets that pivotally support the liftaxle, and two rearward load springs (e.g., air springs) that are mountedto the lift axle. Such lift axle systems can be attached to the vehiclechassis by two forward brackets and two rear brackets. The two forwardbrackets attach the two hanger brackets to the two longitudinal framemembers, and the two rear brackets attach the two load springs to thetwo frame members. Often, however, it may be necessary or desirable toadjust the left-to-right position of the lift axle relative to thevehicle frame during installation (or subsequent service) to ensureproper alignment of the axle. Additionally, it may also be necessary ordesirable to remove and replace one of load springs without having todetach and then reinstall the corresponding rear frame bracket.

FIG. 1 is an isometric view of a portion of a lift axle system 110having a hanger bracket 104 attached to a vehicle frame member 102 by abracket 106 configured in accordance with the prior art. Although FIG. 1illustrates the right (or passenger) side of the vehicle, it will beunderstood that a mirror image arrangement of the hanger bracket 104,the bracket 106, and the frame member 102 exists on the left (or driver)side of the vehicle as well. The bracket 106 includes an upstandingflange that is attached to the frame member 102 by a plurality of bolts108, and a horizontal flange that is attached to the hanger bracket 104by a pair of bolts 118 that extend through elongated holes 114. It willbe noted that both ends of the upper surface of the hanger bracket 104include a plurality of graduated lines or “tick marks” 112 directlyadjacent to an outer edge portion 116 of the bracket 106. Wheninstalling the lift axle system 110 on the vehicle with the bolts 118not fully tightened, the elongated holes 114 enable the lift axle system110 to be moved back and forth in the lateral direction S to center thelift axle system 110 relative to the vehicle frame. When in position,the installers can verify that the lift axle system 110 is properlyaligned by visually inspecting the relative positions of the outer edgeportions 116 of the left and right brackets 106 relative to therespective tick marks 112 on the hanger brackets 104.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of lift axle hanger bracket configured inaccordance with the prior art.

FIG. 2 is a side view of a vehicle having a lift axle system mounted tothe vehicle chassis with frame brackets configured in accordance withembodiments of the present technology.

FIG. 3A is an isometric view of a lift axle system having frame bracketsconfigured in accordance with embodiments of the present technology, andFIG. 3B is a partially exploded isometric view of the frame brackets.

FIGS. 4A and 4B are top and front views, respectively, of a lift axlesystem attached to a vehicle frame with the frame brackets of FIGS. 3Aand 3B.

FIGS. 5A and 5B are inboard and outboard isometric views, respectively,of forward and aft lift axle frame brackets configured in accordancewith another embodiment of the present technology.

FIG. 6 is an inboard isometric view illustrating a range of differentsized forward and aft lift axle frame brackets configured in accordancewith other embodiments of the present technology.

FIGS. 7A and 7B are isometric views of portions of auxiliary suspensionmounting systems configured in accordance with further embodiments ofthe present technology.

DETAILED DESCRIPTION

The following disclosure describes various embodiments of brackets andother structures for attaching lift axle systems and other auxiliarysuspension systems to the chassis of heavy-duty trucks, trailers, and/orother vehicles, and associated methods of manufacture and use. Auxiliarysuspension system mounting brackets configured in accordance with thepresent technology can include forward brackets for attaching axlehanger brackets to longitudinal frame members of a vehicle, and rearbrackets for attaching axle load springs to the frame members. In someembodiments, the forward frame brackets can include physical featuresthat facilitate lateral alignment of the axle relative to the vehicleframe during installation. These physical features can include, forexample, an outer edge portion of each bracket that includes a series ofgraduated steps. When the axle is first installed, the stepped edgeportion of each bracket is positioned adjacent to a locating surface orother prominent feature of the corresponding hanger bracket. Alignmentof the axle can then be readily achieved by visually confirming that therelative position of each of the hanger brackets with respect to thegraduated steps on the corresponding frame bracket is the same on bothsides of the axle. If not, the axle can be moved from one side to theother as needed to center the axle while the attachment fasteners areslightly loose, and then the attachment fasteners can be fully torquedto their final setting.

In other embodiments, rear frame brackets configured in accordance withthe present technology are two-piece brackets having a base portion thatis attached to an upper portion of a load spring, and an upper orupstanding portion that is attached to the adjacent frame member. Ifdesired or necessary, the base portion can be disconnected from theupstanding portion while the base portion remains attached to the loadspring and the upstanding portion remains attached to the frame member.This enables the load spring to be removed from the axle and replaced orserviced without first having to remove the frame bracket from the framemember.

Certain details are set forth in the following description and in FIGS.2-7B to provide a thorough understanding of various embodiments of thepresent technology. In other instances, well-known structures, systems,materials and/or methods often associated with lift axles systems, metalbracketry, heavy duty trucks and other vehicles, etc. are not shown ordescribed in detail in the following disclosure to avoid unnecessarilyobscuring the description of the various embodiments of the technology.Those of ordinary skill in the art will recognize, however, that thepresent technology can be practiced without one or more of the detailsset forth herein, and/or with other structures, methods, components, andso forth. The terminology used below is to be interpreted in itsbroadest reasonable manner, even though it is being used in conjunctionwith a detailed description of certain examples of embodiments of thetechnology. Indeed, certain terms may even be emphasized below; however,any terminology intended to be interpreted in any restricted manner willbe overtly and specifically defined as such in this Detailed Descriptionsection.

The accompanying Figures depict embodiments of the present technologyand are not intended to be limiting of its scope. The sizes of variousdepicted elements are not necessarily drawn to scale, and these elementsmay be arbitrarily enlarged to improve legibility. In some instances,component details may be abstracted in the Figures to exclude detailssuch as position of components and certain precise connections betweensuch components when such details are unnecessary for a completeunderstanding of how to make and use the invention. Additionally, manyof the details, dimensions, angles and other features shown in theFigures are merely illustrative of particular embodiments of thedisclosure. Accordingly, other embodiments can have other details,dimensions, angles and features without departing from the spirit orscope of the present invention. Those of ordinary skill in the art willappreciate that further embodiments of the invention can be practicedwithout several of the details described below. In the Figures,identical reference numbers identify identical, or at least generallysimilar, elements. To facilitate the discussion of any particularelement, the most significant digit or digits of any reference numberrefers to the Figure in which that element is first introduced. Forexample, element 210 is first introduced and discussed with reference toFIG. 2.

FIG. 2 is a left side (i.e., driver's side) view of a heavy-duty vehicle200 having an auxiliary suspension system 210 attached to a chassis 201with brackets configured in accordance with embodiments of the presenttechnology. In the illustrated embodiment, the auxiliary suspensionsystem 210 is a lift axle system, and may be referred to hereinafter asthe lift axle system 210. However, it will be understood thatembodiments of the apparatuses, systems and methods described herein canbe used with other auxiliary suspension systems including, for example,non-lifting axles. The vehicle 200 includes a cab 206 mounted to thechassis 201. The chassis 201 has two laterally spaced-apart,longitudinally extending frame members 202, although only one framemember 202 can be seen in the side view of FIG. 2. In the illustratedembodiment, the lift axle system 210 is attached to the frame members102 behind tandem axles 204 a and 204 b in a “tag” configuration. One orboth of the axles 204 can be drive axles. In other embodiments, the liftaxle system 210 can be positioned between the cab 206 and the axles 204in a “pusher” configuration. Auxiliary axle systems (including both liftand non-lift axles) configured in accordance with the present technologycan be used with single drive axles, double drive axles, triple driveaxles, etc. The lift axle system 210 includes one or more wheels 212rotatably mounted on opposite sides thereof in a conventional manner. Inoperation, the lift axle system 210 can raise the wheels 212 off of theground 208 when the additional support of the lift axle is not needed,and lower the wheels 212 into contact with the ground 208 as shown inFIG. 2 when the extra support of the lift axle system 210 is needed ordesired.

For directional reference in the discussion that follows, it will beunderstood that the vehicle 200 is pointed in a forward direction F andis aligned with a longitudinal axis L. Additionally, it will beunderstood that a vertical axis V extends upwardly at a right angle tothe longitudinal axis L, and that a lateral axis S (not shown in FIG. 2)extends horizontally transverse to the longitudinal axis L. Although thevehicle 200 is depicted as a concrete mixer for purposes ofillustration, the lift axle systems described herein can be used withvirtually any type of heavy duty vehicle including, for example, othertypes of trucks, trailers, etc., in both “tag” and “pusher”configurations, and with both steerable and non-steerable axles.Accordingly, the various embodiments of the present technology describedherein are not limited to use with any particular type of vehicle or inany particular type of axle arrangement unless specifically notedotherwise herein.

FIG. 3A is an isometric view of a lift axle system 210 having a set offrame brackets 312 and 314 configured in accordance with embodiments ofthe present technology, and FIG. 3B is a partially exploded isometricview of the frame brackets 312 and 314 on the left side of the lift axlesystem 210. Referring first to FIG. 3A, in the illustrated embodimentthe lift axle system 210 includes an axle 316 having wheel hubs 318(identified individually as a first wheel hub 318 a and a second wheelhub 318 b) rotatably mounted to opposite end portions thereof in aconventional manner. Although not shown in FIGS. 3A and 3B, wheels canbe mounted to the hubs 318 in a conventional manner. The lift axlesystem 210 further includes a first hanger bracket 322 a positionedtoward the left side of the vehicle, and a second hanger bracket 322 bpositioned toward the right side of the vehicle. Each of the hangerbrackets 322 is attached to a longitudinally-extending frame member (notshown) by a corresponding forward frame bracket 312 (identifiedindividually as a first forward frame bracket 312 a and a second forwardframe bracket 312 b). In the illustrated embodiment, the axle 316 ispivotally coupled to each of the hanger brackets 322 by a correspondingupper control arm 324 and a lower control arm 326. First and second loadsprings 320 a and 320 b, respectively, have lower portions that areattached to opposite sides of the axle 316, and upper portions that areattached to the corresponding frame member by a rear bracket 314(identified individually as a first rear bracket 314 a and a second rearbracket 314 b). In the illustrated embodiments, the load springs 320 areconventional air springs well known in the art which can be inflated ina known manner to lower the lift axle 316, and deflated in a knownmanner for raising the lift axle 316 by means of, e.g., correspondinglift springs. In some embodiments, the lift axle system 210 can be atleast generally similar in structure and function to lift axle systemsdescribed in co-pending U.S. patent application Ser. No. 15/701,369,filed Sep. 11, 2017, and titled LIFT AXLE AUXILIARY SUSPENSION SYSTEMS,now U.S. Pat. No. 10,569,814, which is incorporated herein by referencein its entirety. As those of ordinary skill in the art will appreciate,however, in other embodiments the frame brackets described herein can beused with other lift and non-lift axle systems, and are not limited touse with any particular type of system. Additionally, it will beappreciated that the lift axle systems described herein are but someexamples of auxiliary suspension systems that can be mounted to vehicleframes with the brackets described herein and, accordingly, the terms“lift axle system”, “auxiliary suspension system”, and the like may attimes be used interchangeably herein.

Referring next to FIG. 3B, the forward frame bracket 312 a includes abase portion 331 and an upstanding portion 333 (which can also bereferred to as an “upper portion 333” and the like). In the illustratedembodiment, the base portion 331 includes two horizontally disposed baseplates 330 (identified individually as a first base plate 330 a and asecond base plate 330 b) and two vertically disposed flanges 332(identified individually as a first flange 332 a and a second flange 332b) extending downwardly on opposite end portions thereof. The upstandingportion 333 includes a vertically disposed back plate 328 that extendsupwardly from the horizontally disposed base plates 330 and is supportedon opposite ends thereof by corresponding gussets 335. In theillustrated embodiment, a horizontally disposed flange 337 extendsinwardly from the back plate 328 generally opposite the base plates 330.In the illustrated embodiment, each of the base plates 330 includes anouter edge portion 352 that has a series of graduated steps 350. Morespecifically, the steps 350 (which can also be referred to as tiered oroffset edge portions) can be spaced apart from each other by relativelysmall increments (e.g., equal increments) in the direction of thelateral axis S. For example, in some embodiments the increments can befrom about 0.02 inch to about 0.5 inch, or about 0.05 inch to about 0.25inch, or about 0.1 inch. Additionally, in the illustrated embodiment thesteps 350 on each of the base plates 330 a and 330 b are mirror imagesof each other so that the corresponding steps are aligned with eachother in the longitudinal direction L.

The forward frame bracket 312 a can be fixedly attached to the hangerbracket 322 a by a pair of threaded studs 336 (identified individuallyas a first threaded stud 336 a and a second threaded stud 336 b) thatproject upwardly from an upper surface 338 of the hanger bracket 322 a,In some embodiments, the studs 336 extend through holes in the baseplates 330 that are oversized in at least one direction. For example, inthe illustrated embodiment the studs 336 extend through elongated holes334 (identified individually as a first elongated hole 334 a and asecond elongated hole 334 b) in the base plates 330 and threadablyreceive corresponding nuts 344. In the illustrated embodiment, theforward frame bracket 312 a is also attached to the hanger bracket 322 aby a pair of fasteners, e.g., bolts 342 that extend through elongatedholes 340 (identified individually as a first elongated hole 340 a and asecond elongated hole 340 b) in the vertical flange 332 on each end ofthe frame bracket 312 and threadably engage nut plates 346 on the insideof the hanger bracket 322 a. As illustrated in FIG. 3B, each of theelongated holes 340 and 334 are elongated in the direction of thelateral axis S. For example, the holes 340 and 334 can be elongated fromabout 0.1 inch to about 1 inch or more, or from about 0.2 inch to about0.75 inch. This enables the lift axle system 210 to be moved to the leftor right if needed to align or otherwise adjust the position of the liftaxle 316 relative to the vehicle frame before the nuts 344 and the bolts342 have been fully tightened.

In the illustrated embodiment, the rear frame bracket 314 a is atwo-piece bracket having a base portion 361 and an upstanding portion363 (which can also be referred to as an “upper portion 363” and thelike). The base portion 361 includes a horizontally disposed base plate360 having a first air valve notch 368 toward an inboard side and asecond air valve notch 370 toward the opposite outboard side.Additionally, the base plate 360 includes two countersunk holes 366(identified individually as a first countersunk hole 366 a and a secondcountersunk hole 366 b) configured to receive countersunk fasteners 364(e.g., screws, such as flush head screws) that extend through the holes366 and engage threaded bores 378 (identified individually as a firstthreaded bore 378 a and a second threaded bore 378 b) in a top plate 380of the load spring 320 a to secure the base plate 360 to the top plate380. The base plate 360 further includes square holes 374 (identifiedindividually as a first square hole 374 a and a second square hole 374b) which are countersunk on the backside of the base plate 360. Thesquare holes 374 are configured to receive countersunk fasteners 382(e.g., screws, such as flush head screws; identified individually as afirst countersunk fastener 382 a and a second countersunk fastener 382b) which are trapped between the base plate 360 and the top plate 380and extend upwardly through the square holes 374. The countersunkfasteners 382 can have square shoulders under the heads (similar to atypical carriage bolt) that fit snugly into the square holes 374 toresist turning when nuts 384 are installed and torqued. In otherembodiments, the fasteners 382 can be replaced by threaded studs thatare welded directly to the plate 360 or to the plate 380, or by othertypes of similarly oriented fasteners that do not protrude below thebottom surface of the base plate 360.

In the illustrated embodiment, the upstanding portion 363 of the rearframe bracket 314 a includes a vertically disposed back plate 362 thatextends upwardly from two horizontally disposed base plates 386(identified individually as a first base plate 386 a and a second baseplate 386 b). The base plates 386 are separated by a gap 388 and arereinforced by gussets 390 that extend upwardly between the base plates386 and the back plate 362. Each of the base plates 386 includes athrough hole 376 (identified individually as a first through hole 376 aand a second through hole 376 b) configured to receive one of thefasteners 382. In the illustrated embodiments, the forward framebrackets 312 a and 312 b are identical, or at least substantiallyidentical, to each other, and the rear frame brackets 314 a and 314 bare identical, or at least substantially identical, to each other. Theforward frame brackets 312 and the rear frame brackets 314 can bemanufactured using suitable materials and methods well known to those ofordinary skill in the art. For example, in some embodiments the framebrackets 312 and 314 can be manufactured from steel plate that is cutand formed to shape and then welded together along abutting edgeportions. In other embodiments, it is contemplated that the framebrackets can be manufactured from other materials using other suitablemethods known in the art, such as by machining the brackets from, forexample, steel or aluminum castings, forgings, etc.

FIG. 4A is a top view, and FIG. 4B is a corresponding front view of thelift axle system 210 mounted to the vehicle frame members 202 a and 202b with the forward brackets 312 and the rear brackets 314 in accordancewith an embodiment of the present technology. Referring to FIGS. 3A-4Btogether, to install the lift axle system 210 on the vehicle chassis,the forward frame brackets 312 are attached to the corresponding hangerbrackets 322 in such a way that the lift axle 210 will be able to moveback and forth parallel to the lateral axis S to adjust the position ofthe lift axle system 210 relative to the frame members 202. This isaccomplished by positioning the forward frame brackets 312 on thecorresponding hanger brackets 322 such that the threaded studs 336extend upwardly through the elongated holes 334, and then installing thenuts 344 on the studs 336 and installing the bolts 342 through theelongated holes 340 to engage the corresponding nut plates 346, Then thenuts 344 and the bolts 342 can be tightened enough to remove anyappreciable gaps between the forward frame brackets 312 and the hangerbrackets 322, but still permit side to side movement of the hangerbracket 322 relative to the frame bracket 312 by means of the elongatedholes 340 and 334.

Once the forward frame brackets 312 have been installed on thecorresponding hanger brackets 322 in this manner, the frame brackets 312can be fixedly attached to the frame members 202 by positioning thehorizontal flanges 337 of the respective frame brackets 312 against thelower flanges of the corresponding frame members 202 and installing aplurality of fasteners 404 (e.g., bolts, Huck fasteners, etc.; FIGS. 4Aand 4B). More specifically, the vertically disposed back plates 328 ofthe forward frame brackets 312 can include a plurality of pre-existingholes configured to receive the fasteners 404, and these holes can beused to locate new holes in the frame members 202 for the fasteners 404.Alternatively, both parts can have pre-drilled holes positioned toreceive the fasteners 404, or both parts can initially be blank and thefastener holes can be match drilled in situ. In other embodiments, thebrackets 312 can be welded to the frame members 202. Either way, oncethe forward frame brackets 312 have been bolted or otherwise fastened tothe corresponding frame members 202, the lateral position of the liftaxle system 210 can be adjusted by virtue of the elongated holes 340 and334 as necessary to center or otherwise align the lift axle system 210with respect to the frame members 202. The elongated holes 340 and 334also enable the frame brackets 312 to accommodate different vehicleframe widths. Moreover, the person installing the lift axle system 210can verify that the lift axle system 210 is properly aligned by visuallyinspecting the relative positions of the graduated steps 350 withrespect to the vertical surface 348 of the corresponding hanger bracket322. More specifically, referring to FIG. 4A, if the graduated steps 350include a series of three steps 350 a-350 c, then the position of thesteps 350 relative to the vertical surface 348 should be the same (e.g.,equal, or at least approximately equal) on both sides of the vehicle.For example, if the third step 350 c of the first frame bracket 312 a isflush with the vertical surface 348 on the left side of the vehicle,then the third step 350 c on the second frame bracket 312 a should alsobe flush (or at least approximately flush) with the correspondingvertical surface 348 to ensure that the lift axle system 210 is properlyaligned (e.g., centered) with respect to the frame members 202. If not,the lift axle system 210 should be moved in the lateral direction asrequired to center the hanger brackets 322 with respect to thecorresponding frame brackets 312 before fully tightening the nuts 344and the bolts 342. The visual alignment aid provided by the stepped-edgefeature can eliminate the need for potentially difficult measurements.Additionally, in some embodiments providing the stepped-edge feature inthe frame brackets 312 can eliminate the need to provide specialalignment features on the hanger brackets 322. Accordingly, it iscontemplated that, in some embodiments, the frame brackets 312 can beused to facilitate alignment of a wide variety of auxiliary suspensionsystems having a variety of different hanger bracket configurations.

In other embodiments, the frame brackets 312 and/or the hanger brackets322 can include other features to facilitate visual alignment of thelift axle system 210. For example, FIG. 7A is an outboard isometricview, and FIG. 7B is a front isometric view, of other embodiments of theframe bracket 312. As shown in FIG. 7A, in some embodiments one or bothof the base plates 330 a and 330 b can include one or more holes 710 aand 710 b that are positioned over markings 711 (e.g., numbers, letters,etc.), grooves, or other features formed on or in the upper surface 338of the hanger bracket 322. During installation, the person or personsinstalling the lift axle system 210 can confirm proper alignment byvisually confirming that the features 711 on the upper surfaces 338 ofthe respective hanger brackets 322 which show through the holes 710 inthe corresponding frame bracket base plates 330 are in the same relativeposition on both sides. In further embodiments, as shown in FIG. 7B, afront and/or rear vertical surface 714 of the hanger brackets 322 caninclude a series of graduated marks 712 or other features thatfacilitate side-to-side alignment of the lift axle system 210 by visualcomparison to corresponding features (e.g., the edges of the flanges332) of the frame brackets 312.

Returning to FIGS. 3A-4B, for ease of understanding, attachment of theload springs 320 to the frame members 202 is described below withrespect to the first load spring 320 a, with the understanding the sameprocess applies to attachment of the second load spring 320 b. To attachthe first load spring 320 a to the first frame member 202 a, the baseportion 361 of the rear frame bracket 314 a is separated from the upperportion 363, and the base plate 360 is positioned on the top plate 380of the load spring 320 a with the fasteners 382 extending upwardlythrough the square holes 374 (FIG. 3B). The base plate 360 is positionedso that an air valve 372 a is located in the notch 370 or, in the caseof the second load spring 320 b which has an air valve 372 b positionedon the inboard side of the second frame member 202 b, the air valve 372b is positioned in the notch 368. Accordingly, the rear frame bracket314 a is able to accommodate a load spring having an air valve on eitherthe inboard or outboard side of the corresponding frame member. Next,the countersunk fasteners 364 are inserted through the holes 366 andengaged with the threaded holes 378 in the top plate 380 to fixedlyattach the base portion 361 to the top plate 380. The upstanding portion363 of the rear frame bracket 314 a can then be attached to the baseportion 361 by positioning the base plates 386 on top of the base plate360 so that the fasteners 382 extend upwardly through the holes 376. Thenuts 384 are then threadably installed onto the fasteners 382 and can betightened to full torque.

The rear frame bracket 314 a can then be fixedly attached to the framemember 202 a by positioning the base portion 361 against the lowerflange of the frame member 202 a and installing one or more fasteners,e.g., bolts 406 through the back plate 362 and the frame member 202 a asshown in FIGS. 4A and 4B. More specifically, although not shown in FIG.3A or 3B, the rear frame bracket 314 a can include a plurality ofpre-drilled holes that can be used to locate corresponding holes in theframe member 202 a for receiving the bolts 406. In other embodiments,both the rear frame bracket 314 a and the frame member 202 a can havepre-drilled holes, or both of these structural elements may be undrilleduntil installation and then matched drilled in situ. With eitherapproach, the back plate 362 is fixedly bolted otherwise fixedlyattached to the frame member 202 a to securely attach the upper portionof the load spring 320 a to the frame member 202 a. Because thefasteners 364 of this embodiment are countersunk, the heads of thefasteners 364 do not interfere with the lower flange of the frame member202 a when the base portion 361 is positioned against the lower flangeof the frame member 202 a.

As noted above, one advantage of the rear frame brackets 314 is that theload springs 320 can be removed and replaced without having to detachthe upstanding portions 363 of the frame brackets 314 from the framemembers 202. For example, if the load spring 320 a needs to be removedfor maintenance or replacement after the lift axle system 210 has beenin service, the nuts 384 can be removed from the fasteners 382 so thatthe base portion 361 of the frame bracket 314 a can be separated fromthe upstanding portion 363 while the upstanding portion 363 remainsfixedly attached to the frame member 202 a. This enables the upperportion of the load spring 320 a to be moved downwardly and away fromwith the frame member 202 a for removal from the lift axle 316. As canbe seen with reference to FIGS. 3B and 4A, the nuts 384 should be easilyaccessible by a person working in the proximity of the lift axle system210. Once the upper portion of the load spring 320 a has been detachedfrom the upstanding portion 363 of the frame bracket 314 a, the lowerportion of the load spring 320 a can be detached from the axle 316 in aknown manner and removed, and a new load spring 320 a can then beinstalled by reversing the foregoing process. Although some conventionaldesigns may enable a load spring to be removed without detaching theframe bracket from frame member, these designs may have limitations. Forexample, conventional designs that utilize two studs to attach the loadspring to the frame bracket (one outboard of the frame member and oneinboard) may require notching of the lower flange of the frame member toclear the inboard stud. Embodiments of the present technology, however,can be used with wide flange frame members without this limitation.

FIGS. 5A and 5B are right side (i.e., passenger side) inboard andoutboard isometric views, respectively, of a forward frame bracket 512and a rear frame bracket 514 configured in accordance with otherembodiments of the present technology. Referring to FIGS. 5A and 5Btogether, the forward frame bracket 512 can be at least generallysimilar in structure and function to the forward frame bracket 312described in detail above. In the illustrated embodiment, however, theforward frame bracket 512 includes a horizontally disposed flange 530that is configured to be spaced above the upper surface 338 of thehanger bracket 322. The rear frame bracket 514 is at least generallysimilar in structure and function to the rear frame bracket 314described in detail above. However, in the illustrated embodiment therear frame bracket 514 is a “one-piece” rear frame bracket in which anupstanding portion 563 is permanently attached (e.g., by welding) to abase portion 561. Additionally, in the illustrated embodiment the rearframe bracket 514 includes a vertically disposed riser 522 having anupper edge portion 532 that is configured to be spaced above the uppersurface of the load spring top plate 380.

As can be seen with reference to, for example, FIG. 4B, the framebrackets 312 and 314 described in detail above are configured for usewhen the upper surfaces 338 of the hanger brackets 322 and the topplates 380 of the load springs 320 are to be positioned in contact with,or at least relatively close to, the lower horizontal flange of thecorresponding frame member 202. In other applications, for example, inother applications in which the vehicle has a higher frame height and/ormay be using smaller wheels on the axle, it may be desirable to positionthe lift axle system 210 below the lower flange of the frame members 202by a selected distance, such as a distance ranging from about 1 inch toabout 12 inches, or various distances therebetween. In such embodiments,the frame brackets 512 and 514 illustrated in FIGS. 5A and 5B can beused by positioning the flange 530 and the upper edge portion 532against the lower flange of, e.g., the frame member 202 b (FIG. 4B)before bolting the forward frame bracket 512 and the rear frame bracket514 to the frame member 202 b. Because the riser 522 provides spacebetween the lower flange of the frame member 202 b and the base portion561, a person can easily access bolts 584 a and 584 b to disconnect theupper portion of the load spring 320 b from the rear frame bracket 514without having to disconnect the rear frame bracket 514 from the framemember 202 b. Accordingly, for this reason in some embodiments the rearframe bracket 514 does not have to be a two-piece frame bracket like theframe bracket 314 described in detail above. However, in someembodiments, it may be advantageous for the frame bracket 514 to be intwo-piece form like the frame bracket 314 to, for example, providebetter tool access to fasteners. Although FIGS. 5A and 5B illustrate theforward frame bracket 512 and the rear frame bracket 514 as used on theright side (passenger side) of the vehicle, the same brackets can beused on the left side of the vehicle by simply reversing theirdirection.

FIG. 6 illustrates an inboard isometric view of forward frame brackets612 and 613 superimposed on the forward frame brackets 312 and 512described in detail above to illustrate how the same basic forward framebracket can be used to accommodate a variety of different verticalpositions of a lift axle system relative to the vehicle frame.Similarly, FIG. 6 also illustrates rear frame brackets 614 and 615superimposed on the rear frame brackets 314 and 514 described above tofurther illustrate how this type of rear frame bracket can be used toaccommodate a variety of lift axle mounting elevations.

References throughout the foregoing description to features, advantages,or similar language do not imply that all of the features and advantagesthat may be realized with the present technology should be or are in anysingle embodiment of the invention. Rather, language referring to thefeatures and advantages is understood to mean that a specific feature,advantage, or characteristic described in connection with an embodimentis included in at least one embodiment of the present technology. Thus,discussion of the features and advantages, and similar language,throughout this specification may, but do not necessarily, refer to thesame embodiment. Furthermore, the described features, advantages, andcharacteristics of the present technology may be combined in anysuitable manner in one or more embodiments. One skilled in the relevantart will recognize that the present technology can be practiced withoutone or more of the specific features or advantages of a particularembodiment. In other instances, additional features and advantages maybe recognized in certain embodiments that may not be present in allembodiments of the present technology.

Any patents and applications and other references noted above, includingany that may be listed in accompanying filing papers, are incorporatedherein by reference. Aspects of the invention can be modified, ifnecessary, to employ the systems, functions, and concepts of the variousreferences described above to provide yet further implementations of theinvention.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to,” As used herein, the terms “connected,”“coupled,” or any variant thereof means any connection or coupling,either direct or indirect, between two or more elements; the coupling orconnection between the elements can be physical, for fluid (e.g., air)transfer, logical, or a combination thereof. Additionally, the words“herein,” “above,” “below,” and words of similar import, when used inthis application, refer to this application as a whole and not to anyparticular portions of this application. Where the context permits,words in the above Detailed Description using the singular or pluralnumber may also include the plural or singular number respectively. Theword “or,” in reference to a list of two or more items, covers all ofthe following interpretations of the word: any of the items in the list,all of the items in the list, and any combination of the items in thelist.

The above Detailed Description of examples and embodiments of theinvention is not intended to be exhaustive or to limit the invention tothe precise form disclosed above. While specific examples for theinvention are described above for illustrative purposes, variousequivalent modifications are possible within the scope of the invention,as those skilled in the relevant art will recognize. The teachings ofthe invention provided herein can be applied to other systems, notnecessarily the system described above. The elements and acts of thevarious examples described above can be combined to provide furtherimplementations of the invention. Some alternative implementations ofthe invention may include not only additional elements to thoseimplementations noted above, but also may include fewer elements.Further any specific numbers noted herein are only examples: alternativeimplementations may employ differing values or ranges.

While the above description describes various embodiments of theinvention and the best mode contemplated, regardless how detailed theabove text, the invention can be practiced in many ways. Details of thesystem may vary considerably in its specific implementation, while stillbeing encompassed by the present disclosure. As noted above, particularterminology used when describing certain features or aspects of theinvention should not be taken to imply that the terminology is beingredefined herein to be restricted to any specific characteristics,features, or aspects of the invention with which that terminology isassociated. In general, the terms used in the following claims shouldnot be construed to limit the invention to the specific examplesdisclosed in the specification, unless the above Detailed Descriptionsection explicitly defines such terms. Accordingly, the actual scope ofthe invention encompasses not only the disclosed examples, but also allequivalent ways of practicing or implementing the invention under theclaims. From the foregoing, it will be appreciated that specificembodiments of the invention have been described herein for purposes ofillustration, but that various modifications may be made withoutdeviating from the spirit and scope of the various embodiments of theinvention. Accordingly, the invention is not limited, except as by theappended claims.

Although certain aspects of the invention are presented below in certainclaim forms, the applicant contemplates the various aspects of theinvention in any number of claim forms. Accordingly, the applicantreserves the right to pursue additional claims after filing thisapplication to pursue such additional claim forms, in either thisapplication or in a continuing application.

We claim:
 1. A frame bracket for attaching an auxiliary suspensionsystem to a vehicle frame, the auxiliary suspension system including anaxle having at least one wheel rotatably mounted at each end portionthereof, the frame bracket comprising: at least one aperture configuredto receive a fastener for attaching the frame bracket to the auxiliarysuspension system, wherein the at least one aperture is oversized alongan axis; and at least one physical feature, wherein the at least onephysical feature includes an edge portion having a series of stepsformed thereon, wherein the steps are offset relative to each other inthe direction of the axis, and wherein the steps are configured to bepositioned proximate a physical feature of the auxiliary suspensionsystem to facilitate visual alignment of the axle relative to thevehicle frame during installation of the auxiliary suspension system. 2.The frame bracket of claim 1 wherein the axis is a lateral axis, whereinthe at least one aperture is elongated along the lateral axis, andwherein the steps are shaped and positioned to facilitate lateralalignment of the axle relative to the vehicle frame during installationof the auxiliary suspension system.
 3. The frame bracket of claim 1wherein the auxiliary suspension system further includes a hangerbracket, wherein the axle is movably coupled to the hanger bracket, andwherein the frame bracket further comprises: a horizontally disposedbase plate, wherein the at least one aperture is formed in the baseplate and is configured to receive the fastener for fixedly attachingthe frame bracket to the hanger bracket, wherein the edge portion is anedge portion of the base plate, and wherein the physical feature of theauxiliary suspension system is a physical feature of the hanger bracket.4. The frame bracket of claim 3 wherein the hanger bracket includes avertical surface, and wherein the steps on the edge portion of the baseplate are configured to be positioned relative to the vertical surfaceof the hanger bracket to facilitate visual alignment of the axlerelative to the vehicle frame during installation of the auxiliarysuspension system.
 5. The frame bracket of claim 3 wherein the hangerbracket includes a vertical surface, and wherein the steps on the edgeportion of the base plate are configured to be aligned with the verticalsurface of the hanger bracket to facilitate visual alignment of the axlerelative to the vehicle frame during installation of the auxiliarysuspension system.
 6. The frame bracket of claim 1 wherein the auxiliarysuspension system further includes a hanger bracket, wherein the axle ismovably coupled to the hanger bracket, and wherein the frame bracketfurther comprises: a horizontally disposed base plate, wherein the atleast one aperture is formed in the base plate and is configured toreceive the fastener for fixedly attaching the frame bracket to thehanger bracket; and a vertically disposed flange extending downwardlyfrom the base plate, wherein the vertically disposed flange includes theat least one physical feature of the frame bracket.
 7. The frame bracketof claim 1 wherein the vehicle frame includes a lower flange, whereinthe auxiliary suspension system further includes a hanger bracket,wherein the axle is movably coupled to the hanger bracket, and whereinthe frame bracket further comprises: a horizontally disposed base plate,wherein the at least one aperture is formed in the base plate and isconfigured to receive a fastener for fixedly attaching the frame bracketto the hanger bracket; and a horizontally disposed member spaced abovethe base plate, wherein the horizontally disposed member is configuredto be positioned against the lower flange of the vehicle frame.
 8. Theframe bracket of claim 7, further comprising a vertically disposed backplate extending upwardly from the base plate, wherein the base plateextends outwardly from a first side of the back plate, and wherein thehorizontally disposed member extends outwardly from a second side of theback plate, opposite to the first side.
 9. A frame bracket for attachingan auxiliary suspension system to a vehicle frame, the auxiliarysuspension system including a hanger bracket and an axle having at leastone wheel rotatably mounted at each end portion thereof, wherein theaxle is movably coupled to the hanger bracket, and wherein the framebracket comprises: at least one physical feature shaped and positionedto facilitate visual alignment of the axle relative to the vehicle frameduring installation of the auxiliary suspension system; a horizontallydisposed base plate having a first elongated aperture formed therein,wherein the first elongated aperture is oversized along an axis; and avertically disposed flange extending downwardly from the base plate,wherein the vertically disposed flange includes a second elongatedaperture, and wherein the first and second elongated apertures areconfigured to receive corresponding fasteners for fixedly attaching theframe bracket to the hanger bracket.